Detachable connector for the transmission of drive energy to submersible pile drivers, cut-off equipment or similar work units

ABSTRACT

In order to transmit drive power to piling and cut-off devices (21) or the like usable under water from above the surface of the water to the underwater working device (21), long, heavy and expensive umbilical lines (27,20) with incorporated electric power leads or bunches of long, parallel hydraulic pipes are used which are permanently secured to the working device (21) and must therefore be handled in synchronism therewith, which is not always successful and can lead to damage. The proposal of the invention makes it possible to handle all the umbilical lines (20) and leads (23) including any power transmission means (25) incorporated therein separately from the working device (21) and to have a releasable plug connector (24, 26) at their lower end for direct or indirect connection to the working device (21). This avoids the risk of damage. The connection can be made at any time even outboard and under water.

BACKGROUND OF THE INVENTION

This invention deals with a detachable connector for the transmission ofdrive energy to submersible pile drivers and cut-off equipment orsimilar equipment from above the water surface to the submerged workunits.

For underwater pile driving on the sea floor, the pressure mediumrequired for driving the equipment is supplied through a pressure mediumcircuit with long hoses from above the water surface to the work unit.Because of the flow resistance in the hoses, this is only feasible up toa certain water depth. Either the hose diameter must be increased orseveral hoses must be utilized next to each other, so that the flowresistance can be kept low and the pressure medium pumps can still copewith the additional pressure required to overcome it. Finally, thelimits of feasibility, economy and also handling are reached.

In that case, a submersible drive unit is connected with the equipmentand lowered together with it, supplying pressure medium through a shortclosed circuit, while, for the operation of the drive unit, electricenergy is supplied by means of a long electric power cable from abovethe water surface with now much lower resistance, i. e. energy losses.For the operation of this kind of work unit/drive unit combination, atleast one line for the supply of compressed air to the work unit isusually required in order to compensate for the outer pressure onenclosed empty spaces, and control lines for the control and monitoringof the work unit are also needed.

All these lines are gathered in one conduit only, the umbilical, so thatonly one line need be handled.

The umbilical is heavily reinforced for protection of the internal linesand for loading with tensile forces. It makes the greatest demands onmanufacturing and can cost up to US $1400.00 per meter. It issubstantially more expensive than a lightweight umbilical, as used forthe operation with long hoses described in the beginning, which containsonly control lines but no electric power cables. Depending on theequipment size, the energy to be transmitted and the operating depth, along umbilical with accessories can therefore be more expensive than thepile driver itself. Price and fear of damage discourage its use.

Therefore, again and again, solutions have been tried using even longerand an even greater number of parallel hoses and lighter umbilicals;although these solutions appeared cheaper, failures have been morefrequent because of high risk handling and ensuing higher costs. This isbecause the cost of one hour of downtime of a support ship can be ashigh as US $17,000.00, not counting the water pollution caused by thehose failure.

The costs for the heavy umbilical with winch, as well as for the piledriver/drive unit combination are driven even higher, because, inanticipation of failure of lines in the umbilical and/or one or moremotor-pump units, the umbilical is equipped with a greater number ofelectric power cables and signal lines, or the drive unit is equippedwith a greater number of, or larger, motor-pump units than required,since a quick remedy is currently not possible in the eventuality of afailure.

Moreover, the working speed of the equipment is based on standards whichare common to conventional pile driving above water, which drives up thecapacity of the work unit unnecessarily causing additional costs whichare not commensurate with the derived benefit for underwater work.

The present situation of incurred downtime and damage costs of severalmillion dollars has been tolerated for years. This is technically andeconomically unsatisfactory and this is also unsatisfactory because theexpensive underwater equipment is needed only infrequently and only forshort periods of time, i. e. it cannot be amortized quickly enough.However, the operation with long hoses in the appropriate applicationsis also still unsatisfactory and in need of improvement.

Similar problems occur with other work units, especially with underwatercut-off equipment which will be utilized more and more in future undersimilar conditions in the removal of drilling platforms.

SUMMARY OF THE INVENTION

The object of this invention is to provide a detachable connector forthe transmission of energy to equipment of the aforementioned kind,which makes it possible, at lower equipment cost, to transmit driveenergy more reliably and economically, to improve the ability to replacecomponents and to utilize them more diversely. Therefore, its deploymentis made more economical.

The means for attaining this object is for detachably transmittingelectrical hydraulic energy from a drive unit to a submerged work unit.The drive unit is connected to a support ship, and the detachableunderwater connector includes an underwater socket part and anunderwater plug part. The underwater socket part attaches to a submergedunderwater work unit having a wet connectable electric plug capable oftransmitting electrical signals to the submerged work unit. Theunderwater socket part also has a pair of pressure medium channels incommunication with a corresponding pair of pressure medium channels inthe submerged work unit for transmitting hydraulic energy. Theunderwater plug part is connected to the drive unit and has awet-connectable electrical socket capable of receiving one end of atleast one electrical cable for the transmission of electrical signals.The other end of the electrical cable is connected to an electricalsignal source on a support ship. The underwater plug part also has apair of pressure medium channels in communication with a correspondingpair of pressure medium channels in the drive unit. The wet-connectableelectric socket is capable of receiving the wet-connectable electricplug to transmit electrical signals from the support ship to theunderwater work unit, and the pressure medium channels are capable ofcommunicating hydraulic energy from the drive unit to the underwaterwork unit, when the underwater socket part is detachably coupled to theunderwater plug part according to the invention.

This detachable connector makes it possible to circumvent the risks ofdamage during the handling of the work units by excluding from suchhandling those components which are required for the transmission ofdrive energy and deal with them separately. They can be connected withand detached from the work unit at any time, also outboard andunderwater. This enables the design of lighter underwater drive units,quick inspection and repair, and quick interchange with cheapercomponents.

These advantages derive from the fact that the work unit can remainoutboard and only energy transmitting means (umbilicals etc.) are takenaboard, with or without drive unit, or are separately hoisted up fullspeed, inspected and lowered again. The state of the art is such thatthese components can practically not be separated from the work unitoutboard or at the work site. They have to be disassembled onboard. As awhole unit they can be hoisted up only slowly and lowered againespecially slowly, if they have to be pressurized with air to compensatefor the external water pressure.

Instead of an expensive umbilical one can also utilize a simple cablefor the transmission of drive energy, depending on the method ofoperation, because handling is simpler and gentler. This simpler cablecan be designed as a cheap lightweight umbilical without compressed airlines and without special reinforcement, but with integrated controlcables, provided one does not choose a separate thin control cable orthe signals are transmitted in another way.

On the other hand, for lower power requirements, one can also utilize alightly reinforced cable or lightweight umbilical simultaneously as alifting element to correspond with the smaller and lighter drive units.

Based on the improved ability to replace components, availability ofexcess power and capacity for standby purposes need not be considered inthe equipment layout. Economical designs are possible. In the case ofthe drive unit, several electric-motor-pump-units can be combined intofewer or one single larger unit with lower total, yet appropriate poweroutput, which is favorable from the points of view of construction,weight and handling.

The interconnection of components transmitting drive energy aselectricity or pressure medium is achieved by wet connectable parts,possibly exposed to high water pressure, preferably by means ofmulti-channel single plug-type connectors. Before the operation begins,they are secured against pull-out and torque exerted by the electricmotors either automatically by means of pressure medium or by otheroutside means.

The proposed solutions also improve the operation with long hoses fromabove the water surface. It is also possible to change over alreadyexisting underwater work units and installations partly or completely,as proposed.

The detachable connector according to the invention is economicallyusable up to practically unlimited water depth, and can be used withpile drivers, vibration-, cut-off equipment and other underwater workunits.

Further variations of this detachable connector is described in theclaims. Preferred application examples of the installation are describedbelow in the corresponding drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows schematically a pile driver set on top of a foundation pileof an underwater structure and conventionally connected with the supportship by way of a drive unit.

FIG. 2 shows a representation, similar to FIG. 1, of a vibration piledriver with a smaller, simplified drive unit.

FIG. 3 shows a representation, similar to FIGS. 1 and 2, with of aconventional drive unit installed directly on the pile driver.

FIG. 4 shows a representation, similar to FIG. 3, with a smaller,simplified drive unit.

FIG. 5 shows a schematic representation of a pile driver with a coaxialdrive unit installed on it.

FIG. 6 shows a schematic representation of a pile driver set on top of afoundation pile of a drilling platform and connected with the supportship by means of pressure medium lines.

FIG. 7 shows a side view of the pile driver according to FIG. 6.

FIG. 8 shows a schematic representation of a pile driver with drive unithanging outboard at deck height.

FIG. 9 shows a representation, similar to FIG. 8, in a differentequipment configuration.

FIG. 10 shows a schematic representation of cut-off equipment set on afoundation pile of an underwater structure.

FIG. 11 shows a schematic representation of a smaller, simplified driveunit.

FIG. 12 shows a drive unit according to FIG. 11 with a plug connectionconnected coaxially on the top end of a pile driver or cut-offequipment.

FIG. 13 shows a partial view of FIG. 12 with an electric plug connectionexternal to the plug connection connecting the drive unit.

FIG. 14 shows a partial view of a drive unit composed of several modulardrive units set on a work unit, as in FIG. 12.

FIG. 15 shows a representation, similar to FIG. 12, with a lockable plugconnection.

FIG. 16 shows a partial view of a representation according to FIG. 15with a locked plug connection.

FIG. 17 shows a schematic representation of three interconnected driveunits connected with the underwater work unit by means of lines.

FIG. 18 shows the drive units according to FIG. 17 from below.

FIG. 19 shows a detailed partial view of the pressure medium hoseconnection with the pile driver according to FIG. 7.

FIG. 20 shows a magnified detailed partial view of the top portion ofpile driver similar to FIG. 9.

DETAILED DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a pile driver 1 free standing on top of the foundation pile2 connected with the support ship 3 in the coventional manner. The piledriver 1 is lifted and lowered by the crane 9, boom 10, and lifting rope11 together with the drive unit 22, which is connected by the additionallifting rope 12 with the pile driver 1. The umbilical 18, which connectssupport ship 3 by way of winch 13 and deviating roller 14 with the driveunit 22 for the supply of energy and compressed air or signals, must bemoved in unison during all operations. Inevitably the same applies tothe lines 23 which firmly interconnect pile driver 1 and work unit 22,and which are endangered together with the expensive umbilical 18.

The endangering is minimized by an umbilical 20 supported by a winch 15,and extending to the drive unit 22 where it can be plugged in andunplugged at any time, because the electric power cable and control lineplug connection 24 (similar to FIG. 13) is made only after theendangering action, but at the latest underwater when the pile driver 1is already set on the foundation pile 2. In addition, the umbilical 20is cheaper because it contains only electric power cables and controllines. In addition to the lifting rope 11, instead of the umbilical 18,only the compressed air line 16, which is replaceable at little cost,continues to be connected with the drive unit 22, and from there withthe pile driver 1, because compressed air supply is required from thebeginning of the dive. This gentler handling even makes it possible toinstall a still more favorable electric power line 20a and a separatecontrol line instead of the umbilical 20.

The number of plug connections 24 depends on their transmission capacityand the energy requirement. The plug connections are made with the robottool 8 of the remote controlled underwater vehicle 6 which is connectedwith the support ship 3 by means of line 5.

The vibration pile driver 21 shown in FIG. 2 is connected, in contrastto FIG. 1, with a smaller, simplified and separate drive unit 25. As inFIG. 1, the energy supply of the vibration pile driver 21 is providedfrom the support ship 3 by way of the component winch train 13,deviating roller 14, umbilical 20, electric power line and control lineplug connection 24, drive unit 25 and supply line 23, which isdetachably connected with vibration pile driver 21 by means of thepressure medium and control line plug connection 26.

The supply line 23 and the drive unit 25 with umbilical 20, that is thewhole train of energy transmitting components, can therefore be handledsingly and gently according to its requirements.

Now the drive unit 25 no longer acts as a load carrying element betweenlifting ropes 11 and 12, as shown in FIG. 1. The lifting rope 12 istherefore not required. The drive unit 25 can have a lighter weightdesign because it is not required to carry load. It can now also besuspended from an appropriate tension carrying umbilical 20, therebyeliminating the lifting rope 27.

The plugging in operations are carried out with the help of underwatervehicle 6.

In FIG. 3, the pile driver 1 is powered by a directly mounted,conventional drive unit 17 by way of a small internal closed pressuremedium circuit (not shown).

The energy supply is optimized, similar to FIG. 1, in that the expensiveumbilical 18 is divided up into the compressed air line 16 and thelifting rope 11 carrying the pile driver 1/drive unit 17 combination,with both lines being handled simultaneously, and the umbilical 20,handled separately, now still carrying only electric power and controllines which are detachably connected to the drive unit 17 by means ofthe plug connection 24.

Apart from the cost savings derived from dividing up the umbilical 18and its lowered risk of damage, the advantage of its improvedinterchange possibility remains, as in FIG. 1.

In FIG. 4, a smaller, simplified drive unit 25 is directly connectedwith pile driver 1. In contrast to the variation shown in FIG. 3, thedrive unit 25 is connected as a whole with the pile driver 1 by means ofa detachable pressure medium and control line plug connection 26 (seeexplanations for FIG. 12 and 15). The unplugging of plug connection 26is affected by pulling with the lifting rope 27 or with the umbilical 20or cable 20a. As required one or several drive units 25 can be arrangedaround the pile driver and connected with it. An imbalance iscompensated for by a counterweight 28.

In FIG. 5, the drive unit 25 is connected, in contrast to FIG. 4,directly and coaxially to the upper portion of the pile driver 1. Thisis why two ropes 29 are utilized which are connected at their lower endsto the sides of the upper portion of pile driver 1, and at their upperends to the lifting rope 11, without contacting the drive unit.Compressed air is supplied by means of line 16. The drive unit 25 isconnected with a detachable plug connection 26, as described in FIG. 4.It is supported on the pile driver by means of a spring 30 whichcushions shocks. This arrangement is favorable for symmetry reasons.

FIG. 6 shows a pile driver 1 which is connected with the support ship 3by means of long pressure medium lines 23 next to a control line 4, byway of the deviating roller 14 and the winch 13. The pile driver 1 isconnected with the support ship 3 for the supply of compressed air bymeans of line 16 by way of the winch 15, and for lifting and lowering bymeans of lifting ropes 11 and 29.

For connecting lines 23 with the pile driver 1, a detachable pressuremedium and control line plug connection 26 with distributor piece 31 isprovided. The desired gentle handling is provided by the possibility ofseparating the lines 23 and the control cable 4 from the pile driver 1.

In FIG. 7 are shown, as a side view of FIG. 6, several parallel pressuremedium lines 23 and a control line 4 in the center, all of whichterminate at the distributor piece 31. This line/cable bundle isdirectly connected with the support ship 3 or with an intermediateunderwater drive unit. The large number of hoses 23 with small diameterare used in order to avoid using a very expensive type of hose withcorresponding large diameter for the feed and return lines. As analternative, standard hoses in commercially available short lengths arecoupled together. But since the latter do not measure up to the roughhandling and since the many couplings often leak, trouble arises, andfrequently in the vicinity of the pile driver. To remedy thisdifficulty, the pile driver 1, together with the firmly affixed hoses,has to be lifted up in order to exchange the damaged hose pieceoutboard, or the pile driver has to be lifted onboard and laid down ondeck.

According to the invention the repair of such damage is simpler andachieved with greater certainty, because the lightweight hose bundle canbe separated at the plug connection 26 and lifted up separately by meansof the lifting ropes 32 at any time, while the work unit remainsunderwater or outboard. See FIGS. 8 and 9.

FIG. 8 shows a pile driver 1 held outboard in a fixture 33. The linesare connected or disconnected during the short period of time at theship's side after the pile driver has been lifted from the deck andswung outboard, or after it has been lifted up from below. The latter isimportant if the plug connection is equipped with a lock which has to beactuated by remote control from an underwater vehicle, and if thevehicle is defective, so that the separation cannot be affectedunderwater. This is done here so that the sensitive parts can beseparated before the dangerous placement on deck.

The arrangement shown in FIG. 9 corresponds to that of FIG. 8 exceptthat here the lines 4 and 23, feeding directly from the winch 13 oralternatively by way of the deviating roller 14, are connected to theside of the freely and outboardly hanging pile driver 1 which is easilyaccessible from the ship's side in order to make use of the invention'sadvantages.

Corresponding with the diverse application possibilities, FIG. 10 showsunderwater cut-off equipment 50 which is placed on top of a drivenfoundation pipe pile 51 and whose shaft 52 with the cut-off tool 53protrudes into it, so that it can be cut off below the sea floor insection C. The cut-off equipment 50 is driven by an underwater driveunit, which is powered electrically or hydraulically from above thewater surface. It is supplied conventionally, depending on type ofdrive, either by means of an umbilical or long pressure medium lines 23including control line.

In both cases, according to the invention the cut-off equipment 50 isfirst handled without energy supply lines. They are connected later.Since cut-off equipment consumes very little power, equipment needed forobservation such as an underwater vehicle 6 with television cameraincluding lifting equipment can be utilized at low cost. Thus, electricenergy for the electric-hydraulic drive unit on the cut-off equipment 50and signals are preferably supplied to the cut-off equipment 50 by meansof the umbilical 5, the launch cage 19 for the underwater vehicle 6 andone or two connection lines 7 connected by means of an electric plugconnection 24.

If long pressure medium lines 23 supply the drive energy from thesupport ship 3 to the cut-off equipment 50, then these follow the samesupply path. They terminate in a pressure medium and control line plugconnection 26 at the cut-off equipment 50.

Furthermore the cut-off equipment 50 is connected with the support ship3 by means of the lifting line 11 and the supply line 16 for compressedair or cutting medium.

In addition to the advantages explained above, there are those ofutilizing existing components.

FIG. 11 shows a lightweight drive unit 25. It consists of an underwaterelectric motor 34, a pressure medium pump 35 and a pressure medium tank37. These modular components are joined together by means of a couplingpiece 38 to establish a drive unit. The electric motor 34 is connectedwith its pedestal 39 to the upper part, the pressure medium pump 35 withits flange 40 to the lower end and the pressure medium tank 37 at theflange 41 of coupling piece 38. The flange 41 is shimmed with a slightlyelastic and flexible material in order to dampen shocks to the electricmotor 34 and to bridge machining tolerances between connecting surfacesfor lines 12 and 13 when, instead of these, couplings with machinedsurfaces are used to ensure leak tight connections. See FIGS. 12, 14, 15and 17.

A valve block 36 is attached to the pressure medium pump for therequired operating controls. Pressure medium flows from the flexibleconnection 42 through valve block 36 to pressure medium pump 35 and thenflows pressureless in short circuit loop either completely or partiallyback to the pressure medium tank 37 through flexible connection 43, orflows either completely or partially through connection 44 to the workunit and back to pressure medium tank through connection 45. A pressureequalization cylinder 46 with floating piston 47 communicates throughopenings 48 with the external water on the one side and with thepressure medium on the other. It ensures pressure is equalized betweenexternal water and pressure medium tank.

The energy is supplied by means of the umbilical 20 which is, because ofthe lightweight drive unit 25, simultaneously the lifting element. Thecontrol line 49, exiting from the umbilical 20 or coming separately fromabove, continues to the work unit.

By way of dashed lines it is shown how two drive units may be joined ina simple manner.

In FIG. 12, the drive unit 25 is directly and coaxially connected to thetop of the work unit (1, 21 or 50) by means of a pressure medium andcontrol line plug connection 26.

The plug connection 26 consists of the plug part 54 which is fastened tothe drive unit and the socket part 55. The plug part contains pressuremedium channels 56 and 57 which continue on in socket part 55 andterminate in hose connection 58 and 59 which feed pressure medium intoand return the same from the work unit. The channels have check valves60 which prevent oil from leaking out and water from entering into thesystems when unplugged.

The control lines 49 are connected in the plug part 54 to a coaxial,wet-connectable electric socket 61, whose plug 62 is located in socketpart 55, and which connects control lines 49 with the work unit. Thesupport of socket 61 is preferably elastically displaceable in thetransverse direction in order to avoid problems caused by off-centeringof the connecting parts 54 and 55.

The electric plug connection 61/62 is made simultaneously with thepressure medium connection 54/55. For work units 1, 21, which aresubject to vibrations, the socket part 55 may be mounted in a flangering 63 and spring loaded with a spring 30. The plug connection isplugged in by the weight of the drive unit. As spaces 64, 65 becomesmaller during plugging in, or fluctuate in size because of springaction, the displaced water escapes through openings 66 and 67.

In order to avoid damage to the sealing surface on plug part 54, aprotective skirt 69 is provided which has a large guide cone 68 on itslower end facilitating plugging parts 54 and 55 together.

The lifting element is the umbilical 20 itself which is protectedagainst excessive bending by a bending resistant sleeve 70. It must becapable of unplugging plug part 54 by overcoming the small forces due toretentive connections. Otherwise a lifting rope will be used.

FIG. 13 shows an embodiment according to FIG. 12, where the electricsocket part 61 with plug 62 for control cable 49 is relocated to theoutside and is connected to the work unit 1, 21, 50 by means of line 95,thereby simplifying the interior of plug connection 26. Since parts 61and 62 are connected to spring loaded socket part 55, they are alsospring loaded.

The coaxial cylindrical pin of plug part 62 has as many ring contacts 96as there are signals to be transmitted, provided there are no facilitiesfor information processing and transmission on work unit 1, 21, 50 thatallow several different signals to be transmitted through a single ringcontact 96.

If control line 49 contains a compressed air line, then compressed aircan be transmitted through the hollow plug part 62 and a correspondinglydesigned socket 61 to the work unit. In this case check valves 60 are tobe provided in both parts as described in FIG. 12.

Plug 62 is plugged in by the underwater vehicle 6, as explained underFIG. 2, and unplugged together with the drive unit 25 during unpluggingof plug connection 26 by pulling on the umbilical. If required, the plugconnection parts 61/62 can be locked together, e.g. similar to FIG. 15and FIG. 16.

In FIG. 14 two interconnected drive units 25 are connected to the top ofthe work unit (1, 21, 50) by means of a distributor piece 31 and thepressure medium and control line plug connection 26. The distributorpiece combines pressure medium coming from the pressure medium pumps ofdrive units 25 in channels 71 and 72 into channel 73 and feeds itthrough channel 56 and through plug connection 26 to the work unit (1,21, 50). Pressure medium coming from the latter through channel 57 tochannel 74 and distributed to channels 75 and 76 is returned to thepressure medium tanks of the two drive units 25.

FIG. 15 shows, in contrast to FIG. 12, a pressure medium and controlline plug connection 26a with a locking device 77 which simultaneouslyserves as a pulling device assisting in securely plugging the two partstogether. The parts 54a to 69a of plug connection 26a correspondfunctionally with those of plug connection 26 of FIG. 12. They aretherefore not described again here.

The plug connection 26a is shown just before the plugging in operation.The socket part 55a is already engaging the guide cone 68a of plug part54a and the locking hook 78 is about to swivel and hook on belowshoulder 81 as piston rod 79 of cylinder 80 is retracted. As piston rodis retracted further, parts 54a and 55a, and simultaneously electricsocket parts 61a and 62a, are pulled together by the pulling action ofthe locking hook which rides in guide 88, and which finally firmlytensions them together unless the weight of the drive unit 1 issufficient to effect this by itself. Since the contact areas are pressedtogether, any torque created during starting and running of the electricmotor is absorbed by friction in the contact areas.

The locking mechanism 77 is actuated by control valve 81 whose controlrod 82 is manipulated underwater by underwater vehicle 6 or othersuitable means. In order to retract piston rod 79, pressure medium issent from the high pressure accumulator 84 to the lower chamber ofcylinder 80 through line 83, while simultaneously the displacedhydraulic fluid from the upper chamber of cylinder 80 is sent throughline 85 to the low pressure accumulator 86.

Unlocking occurs through a spring (not shown), which is located, e.g. inthe upper chamber of cylinder 80, and which pushes the piston rod in theinitial position; simultaneously lines 83 and 85 are connected with thelow pressure accumulator 86 transfering the required pressure medium.

If there is insufficient pressure medium in accumulators 84 and 86, i.e.if pressure falls below the lower threshold, it is replenished throughcheck valves 87 from the closed pressure medium circuit. Conversely, anexcess of pressure medium is released from the accumulator 84 or 86 tothe pressure medium circuit through pressure relief valves (not shown).

The check valves 87 are placed in the closed pressure medium circuit ofthe work unit (1, 21, 50), as functionally required: For the highpressure accumulator 84 in pressure channel 56a, and for the lowpressure accumulator 86 in return channel 57a.

The drive energy is supplied by means of the umbilical 20 or separateelectric power cables and control lines.

If required, a spring 30 as shown in FIG. 12 can be included in thisplug connection also. FIG. 16 shows a partial view of plug connection26a with locking hooks 78 of which there are three distributed on thecircumference to ensure uniform pull and clamping force, and alsofriction force to counteract torque created during starting and runningof the underwater electric motors.

The three drive units shown in FIG. 17, interconnected to producegreater drive energy, are detachably connected with the work unit 1, 21,50 by means of a distributor piece 31, as explained for FIG. 14,pressure medium lines 44 and 45, control line 49 and plug connection26a. The pressure medium lines 44 and 45 supply and return,respectively, pressure medium to and from work unit 1, 21, 50 by meansof channels 56a, 58a and 57a, 59a, respectively.

Electrical energy is supplied by the umbilical 20 to the electric powerand control line plug connection 24, from where it is distributed to theelectric motor of each drive unit 25 by means of lines 89. The controlline 49 also branches off from the plug connection 24.

The drive units 25 with plug connection 26a are raised and lowered bylifting ropes 32 and 27 and, after unplugging plug connection 26a, canbe handled as one single assembly, separately from the work unit 1, 21,50.

The advantages of this configuration correspond to those described abovein reference to FIGS. 2, 7 and 8.

FIG. 18 shows how channels 92 and 91 are arranged in distributor piece31, collecting pressure medium from drive units 25 and conveying it toconnection 44, or distributing returning pressure medium from connection45 to drive units 25. Also, channels 91, by virtue of interconnectingand connecting with pressure medium tanks 37 of drive units 25, ensurethat pressure medium tanks are communicating pressure medium with eachother.

Additionally, each individual drive unit 25 is connected to thedistributor piece 31. It firmly connects them to each other to establisha single load bearing construction unit. If extended outwardly, it canalso serve as the base for the protective skirt 93 indicated by dashedlines.

The distributor piece 31 contributes significantly to the desired lightweight and economic design of the detachable connector.

In contrast to FIGS. 13 and 16 where the drive units 25 are directlyconnected with distributor piece 31, FIG. 19 shows in more detail anapplication according to FIGS. 6 and 7 where a plurality of pressuremedium lines 23 are connected with channels 44 and 45 which continue onthrough plug connection 26a to work unit 1, 21, 50 by way of connections58a and 59a.

The compressed air line 16 is separate, unless the plug connection 26ais to be plugged in or unplugged outboard but not underwater. In thiscase the compressed air line 16 is connected as shown and additionalchannels (not shown) are provided inside the plug connection 26a.

The distributor piece 31 can, of course, also be arranged at the upperend of lines 4 and 23, in order to provide an interface for equipmentcomponents suitable for the particular operation at hand. The advantagesof this application are already described above in reference to FIGS. 6and 7.

FIG. 20 shows a centrally connected lifting rope 11 and distributorpiece 31/plug connection 26a combination connected on the side of workunit 1, 21, 50 as in FIG. 9, and the distributor piece 31 in connectionwith lines 16, 23 and 49 according to FIG. 19. The lines and liftingropes 32 are laid down on a device 95 which safeguards against excessivebending and which is affixed to distributor piece 31.

An alternative possibility for affixing the parts combination is shownby way of dashed lines.

The advantages according to this invention can be favorably applied tothe present diverse deployment practice of underwater work units. Theyshall be useful for the already anticipated deployment of similarequipment.

We claim:
 1. A detachable underwater connector for detachablytransmitting electrical and hydraulic energy from a drive unit to asubmerged work unit, wherein the drive unit is fixedly connected to asupport ship afloat on a body of water, the detachable underwaterconnector comprising:an underwater socket part attached to a submergedunderwater work unit having a wet-connectable electric plug capable oftransmitting electrical energy to the submerged work unit, theunderwater socket part also having a pair of pressure medium channels incommunication with a corresponding pair of pressure medium channels inthe submerged work unit; and an underwater plug part connected to thedrive unit having a wet-connectable electric socket capable of receivingone end of at least one electrical cable for the transmission ofelectrical energy, wherein another end of the electrical cable isconnected to an electrical source on a support ship, the underwater plugpart also having a pair of pressure medium channels in communicationwith a corresponding pair of pressure medium channels in the drive unit;and wherein the wet-connectable electric socket is capable of receivingthe wet-connectable electric plug to transmit electrical energy from thesupport ship to the underwater work unit, and the pressure mediumchannels are capable of communicating hydraulic energy from the driveunit to the underwater work unit, when the underwater socket part isdetachably coupled to the underwater plug part.
 2. The detachableunderwater connector of claim 1 wherein the drive unit is situated onthe support ship and further comprises at least one pair of hydrauliclines for the transmission of hydraulic energy, each hydraulic linehaving a top end and a bottom end, the pair of hydraulic linescomprising a supply hydraulic line having its top end connected to thedrive unit on the support ship and a return hydraulic line having itstop end connected to a hydraulic fluid return for the drive unit on thesupport ship and each hydraulic line bottom end connected to thedetachable underwater connector.
 3. The detachable underwater connectorof claim 1 wherein the drive unit is situated underwater and a supplyline remotely connects the drive unit to the underwater work unit by wayof the detachable underwater connector.
 4. The detachable underwaterconnector of claim 1 wherein the drive unit is attached to and mountedon the underwater socket part of the detachable underwater connector. 5.The detachable underwater connector of claim 1 wherein each pressuremedium channel of the underwater plug part has a check valve therein. 6.The detachable underwater connector of claim 1 further compromising alifting umbilical and wherein the detachable underwater connector isdetachably coupled and sealed by the weight of the underwater plug partdescending over the underwater socket part, and is detachable byexerting a lifting force on the lifting umbilical.
 7. The detachableunderwater connector of claim 1 further compromising a locking devicehaving a locking hook pivotally mounted to the underwater plug part andengageable with a shoulder protruding from the underwater plug part,wherein the locking device is actuated by a control valve.
 8. Thedetachable underwater connector of claim 7 wherein the control valvecomprises a control rod to actuate a pressure cylinder for retracting apiston rod to pivotally swivel the locking hook of the underwater plugpart to the shoulder of the underwater socket part.
 9. The detachableunderwater connector of claim 8 wherein the pressure cylinder ispressurized by one of a high gas pressure medium accumulator and a lowgas pressure medium accumulator.
 10. The detachable underwater connectorof claim 1 further comprising a distributor piece having an upper endand a lower end, the distributor piece lower end attached to an upperend of the underwater plug part, and the distributor piece upper endconnected to two interconnected drive units, whereby the distributorpiece combines and distributes pressure medium from the twointerconnected drive units to the underwater work unit.
 11. Thedetachable underwater connector of claim 1 wherein the underwater socketpart and the underwater plug part each further comprises an additionalchannel for communicating compressed air therethrough.
 12. Thedetachable underwater connector of claim 7 further comprising anoutboard fixture mounted to the support ship for receiving theunderwater work unit and allowing above water disengagement of thelocking device prior to placement of the work unit on a deck of thesupport ship.
 13. The detachable underwater connector of claim 1 whereinthe underwater socket part is mounted within a flange ring having abiasing spring therein to outwardly bias the underwater socket part tocompensate for vibrations from the work unit.
 14. The detachableunderwater connector of claim 1 wherein at least one water escapeopening is provided in the underwater socket part communicating betweenan interior of the underwater connector and the exterior of theunderwater connector to displace water as the underwater plug part iscoupled to the underwater socket part.
 15. The detachable underwaterconnector of claim 1 further comprising a protective skirt placed aboutthe underwater plug part and having a guide cone at its lower end tofacilitate the coupling of the underwater plug part to the underwatersocket part.
 16. The detachable underwater connector of claim 1 whereinthe wet-connectable electric plug and socket are positioned on theexterior of the detachable underwater connector.
 17. The detachableunderwater connector of claim 1 wherein the wet-connectable electricplug and socket have a plurality of ring contacts corresponding to anumber of desired signals to be transmitted.
 18. The detachableunderwater connector of claim 1 further comprising a remote controlledunderwater vehicle having a robot tool to guide the coupling of theunderwater plug part to the underwater socket part.
 19. The detachableunderwater connector of claim 18 wherein the underwater vehicle furthercomprises a camera and communication system to assist in the couplingand decoupling of the detachable underwater connector.
 20. Thedetachable underwater connector of claim 1 wherein the underwater socketpart and the underwater plug part are wet-connectable.
 21. A method oftransmitting drive energy from a support ship to an underwater work unitcomprising the steps of:connecting an umbilical between an electricalsource on a support ship and a submersible drive unit for transmittingelectrical power to the submersible drive unit; assembling a hydraulicplug and an electric socket to the submersible drive unit fortransmitting hydraulic and electrical energy to an underwater work unit;lowering the umbilical and drive unit assembly, apart from theunderwater work unit, from the support ship to the underwater work unit;positioning and connecting the umbilical and drive unit assembly to theunderwater work unit, wherein the hydraulic plug and the electric socketattached to the drive unit are aligned with a hydraulic socket and anelectric plug on the underwater work unit by engaging a guide cone onthe hydraulic plug for facilitating the connection; and further loweringthe umbilical and drive unit assembly until a connection is completebetween the drive unit and the underwater work unit such that theconnection can withstand high water pressure.